using System;

[Obsolete("Replace with a better exception someday.")]
internal sealed class ToDoException : Exception {
    public ToDoException() : base() {}
    public ToDoException(string message) : this(message, null) {}
    public ToDoException(string message, Exception innerException) : base(message, innerException) {}
}


class App {
   static void Main() {
      throw new ToDoException("Something went wrong.");
   }
}